[Patent Literature 1] JP 2006-047271 A
For instance, Patent Literature 1 describes an instrument panel provided with a liquid crystal display apparatus to display information. The liquid crystal display apparatus can be recognized by a viewer through an opening portion made of light transmissive texture provided in a meter dial plate. The opening portion in the meter dial plate has a peripheral edge provided with a gradation layer with printing or transfer.
The Inventors examined the use of such gradation with printing described in Patent Literature 1 to a design in a display apparatus. That is, the gradation with printing is applied to a light output face having a belt-like shape in an extended direction to enable a light luminous region formed by the light output face to provide a luminance that decreases in the extended direction from a central portion to each of both end portions. The Inventors however found it difficult for the gradation with printing to provide a smooth or continuous change in luminance of the light luminous region for the following reason.
To be specific, the above printing achieves the gradation by changing the magnitude or density of dots obscuring light. The printing generally limits the number of gradation steps to be expressed or achieved. As a result, when the printing is applied to a light output face so as to express the gradation of light and shade in an extended direction, the change of light and shade is apt to be in a stepwise expression. This eventually causes the change in quantity of the light outputted from the extended direction of the light output face to be stepwise. Thus, the printing seems to be difficult to express the gradation which decreases luminance smoothly or continuously in the light luminous region.